RE: [Discuss-gnuradio] UDP source block in GRC
Yes, if I remember it right the executor only checks a source for output space and then calls work. If the work function doesn't produce any output it's broken according to the executor code. /Ulrika -Original Message- From: discuss-gnuradio-bounces+ulrika.uppman=foi...@gnu.org [mailto:discuss-gnuradio-bounces+ulrika.uppman=foi...@gnu.org] On Behalf Of Mattias Kjellsson Sent: Saturday, April 10, 2010 6:41 PM To: Discuss-gnuradio@gnu.org Subject: Re: [Discuss-gnuradio] UDP source block in GRC Judging by the code in gr_block_executor.cc lines 291- 321, I think that the source didn't report any sample- production to the scheduler. Feel free to correct this statement, and/or give a lengthier explanation. //Mattias ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
RE: [Discuss-gnuradio] IQ imbalance...
Hi Matt Can you please confirm by input level you are referring to the input to the transceiver daughterboard? I am using the XCVR2450, for over-the-air reception. The input level (to the XCVR2450 at the receiver) would have been roughly: Tx Power (max. 20 dBm as per http://www.ettus.com/downloads/er_ds_transceiver_dbrds_v5b.pdf) + Tx Ant. Gain (3dBi) - Free Space Loss (at least 46dB for 2m separation and 2.4 GHz freq.) + Rx Ant. Gain (14 dBi) As far as I can tell based on the above (presuming the 20 dBm transmit power is based on max. gain setting for the Transmitting XCVR2450), the largest signal I could have at the Rx port after the Rx antenna is: 20 + 3 - 46 + 14 = -9 dBm So, if this is the case, I presume all was safe regardless of the chosen Rx gain setting for the receiving daughterboard. Can you please confirm if this would be the case, as I am encountering inconsistent behaviour with my equipment (such as the unrepeatable error mentioned earlier, and occasional fails to lock at 5 GHz without first trying to lock to a much lower frequency). Thanks Ian. -Original Message- From: Matt Ettus [mailto:m...@ettus.com] Sent: Monday, 12 April 2010 3:04 PM To: Ian Holland Cc: discuss-gnuradio@gnu.org Subject: Re: [Discuss-gnuradio] IQ imbalance... As long as the input level is in the safe range, having too much gain would probably not damage anything. On the WBX, however, too much gain with a strong but normally safe level might be a problem. Matt On 04/11/2010 05:01 PM, Ian Holland wrote: Hi Matt Having seen your reply, I realise I was not clear in my original post. At the time I observed this error, it was even at the output of the RRC filter, i.e. prior to the MM synch. and Costas loop. The strange thing is, now I am unable to repeat this problem. Instead, now I see clipping of both the I and Q components when I increase the Rx gain beyond a particular level. While on this matter, is there any risk of damaging the equipment by simply setting the Rx gain too high, or is clipping the only consequence? Ian -Original Message- From: Matt Ettus [mailto:m...@ettus.com] Sent: Friday, 9 April 2010 11:37 PM To: Ian Holland Cc: discuss-gnuradio@gnu.org Subject: Re: [Discuss-gnuradio] IQ imbalance... On 04/08/2010 09:16 PM, Ian Holland wrote: Hi All I am using a pair of USRP2s, each equipped with a XCVR2450, for transmission over-the-air of an RRC-filtered BPSK signal. The Tx antenna has 3dBi gain, and the Rx antenna has 18 dBi gain. The transmitted signal is at maximum amplitude, with gain set to 30 dB. The clocks on each end of the link are running from the internal oscillators - i.e. the clocks are not locked. At the receive side, using an MM synchroniser and Costas loop, I am able to see a BPSK constellation at the receiver when the Rx Gain setting is 30 dB. The amplitude of the constellation points is around 0.15 in this instance. However, when I increase the Rx Gain beyond 33 dB (in which case the constellation is centered around +/- 0.2 on the scope sink), there seems to be a large IQ amplitude balance, whereby the I signal is much stronger. Indeed, the Q signal disappears entirely when the Rx Gain is above around 36 dB. Is this expected behaviour, and if so, can anyone please explain why this is expected to occur? I'm not sure exactly what you're describing here, but I am pretty sure it is not what I would call IQ imbalance. IQ imbalance would show up before any frequency translation, so at the Costas loop output is not where you would see it. The purpose of a costas loop is to track the phase of the incoming signal. That means that the majority of the energy in a BPSK signal will be in I and little will be in Q when the loop is locked. The stronger the signal and the better the SNR, the smaller the Q amplitude will be relative to the I signal. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Spectrum at 1 GHz
I have a query regarding flow graph in GRC. I am trying to get spectrum from DBS_RX daughter board using GRC. I have used three blocks as USRP2 Source -- FFT Filter -- FFT Sink They have following parameters, USRP2 Source: Decimation 1M Frequency 1G Gain (dB) 0 FFT Filter: Decimation 1 Taps firdes.complex_band_pass(1.0, 3000, -0.05e3, 0.05e3, 5, firdes.WIN_HAMMING, 0) FFT Sink: Sample Rate 2K Baseband Frequency 1K FFT Size 512 Refresh Rate 30 I need to display shows frequency spectrum centered at 1 GHz. Since I am using decimation of 1M, the frequency is lowered down to 1K. I filter it using FFT bandpass filter with 100 Hz bandwidth. The fft sink shows spectrum at around 1 KHz. The problem is if I do not use decimation, the GRC seems to be very slow (may be processing 1 GHz at GHz sample rate is too much). I need to make a FFT plot showing spectrum at 1 GHz. How Can I accomplish this? Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Using a custom block
On Sun, Apr 11, 2010 at 04:55:23PM -0400, Kurt Holmquist wrote: I'm looking for some information or references on what to do _after_ doing everything in the how to write a block tutorial in order to be able to access this block from other GNU radio python programs, for example changes to environment variables or whatever will be needed. Is http://gnuradio.org/redmine/wiki/gnuradio/TutorialsWritePythonApplications enough? If not, perhaps your questions are too specific for a tutorial and you might want to ask them directly. I also would like to know what to put into the importfrom gnuradio import blks2/import element in the GRC block XML file so that I can use my custom blocks in GRC. Have a look at how the GRC blocks are defined in gr-howto..., that should clear things up. Good luck, MB -- Karlsruhe Institute of Technology (KIT) Communications Engineering Lab (CEL) Dipl.-Ing. Martin Braun Research Associate Kaiserstraße 12 Building 05.01 76131 Karlsruhe Phone: +49 721 608-3790 Fax: +49 721 608-6071 www.cel.kit.edu KIT -- University of the State of Baden-Württemberg and National Laboratory of the Helmholtz Association pgpVCO0QovBho.pgp Description: PGP signature ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] warning: broken pipe -- some output may be lost
Hi,I use file sink in GRC and Random Source,and want to see the data with
read_short_binary.m in Octave, but it appears like this:octave:10
a1=read_short_binary('a.dat',1e5)
warning: broken pipe -- some output may be lost.
So what's wrong?
Thank you.
Brooke
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[Discuss-gnuradio] LNA, frequency mixer and oscillator
Hi all, I have a USRP2 and a BasicRX. I am new to GNURadio and I am still learning. I have successfully tested the USRP2 with BasicRX. What I have read so far the BasicRX is capable of receiving RF signals from 1-300MHz. But on the FFT window generated by the GRC, it will only display up to 100MHz, limited by the maximum samples. I have searched through the discussion list that the frequency is wrapped and the BasicRX needs a frontend RF circuit. Basically I will need a LNA, a frequency mixer and an oscillator. To my understanding, if I multiply the RF input signal with 100MHz, the whole band ranging from 100MHz - 200MHz will be brought down to 0-100MHz. So I can display it to the FFT window. If I want to scan 200MHz-300MHz, I shall multiply the RF signal with 200MHz. Please correct me if I'm wrong. I have been browsing minicircuits to get the parts needed and I'm not sure if I got everything right. As for the LNA, I have the ZFL-1000LN+ http://www.minicircuits.com/cgi-bin/modelsearch?model=ZFL-1000LN%2Bsearch_type=info For frequency mixer, I have found the ZFM-3+ http://www.minicircuits.com/cgi-bin/modelsearch?model=ZFM-3-S%2Bsearch_type=info For oscillator, I have found the ZX95-200+ http://www.minicircuits.com/cgi-bin/modelsearch?model=ZX95-200%2Bsearch_type=info Are these components correct and enough for me to build the RF frontend? Thank you for your answers. Regards, Ahmad Zaki Yaacob ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
RE: [Discuss-gnuradio] Spectrum at 1 GHz
Hi Umair I believe the decimation factor you have chosen is beyond the maximum allowed (I think, from memory this is 512, which is well less than 1M = 1 times 10^6). It seems you are trying to sample the passband signal to show a spectrum at 1 GHz, however a digital-down conversion is performed at the receiver, so you should see a signal at baseband. You should not need to use such a high sampling rate - ideally, Nyquist rate (based on the signal bandwidth when downconveted to baseband) will suffice. Regards Ian. -Original Message- From: discuss-gnuradio-bounces+ian.holland=rlmgroup.com...@gnu.org [mailto:discuss-gnuradio-bounces+ian.holland=rlmgroup.com...@gnu.org] On Behalf Of Umair Naeem Sent: Monday, 12 April 2010 4:59 PM To: discuss-gnuradio@gnu.org Subject: [Discuss-gnuradio] Spectrum at 1 GHz I have a query regarding flow graph in GRC. I am trying to get spectrum from DBS_RX daughter board using GRC. I have used three blocks as USRP2 Source -- FFT Filter -- FFT Sink They have following parameters, USRP2 Source: Decimation 1M Frequency 1G Gain (dB) 0 FFT Filter: Decimation 1 Taps firdes.complex_band_pass(1.0, 3000, -0.05e3, 0.05e3, 5, firdes.WIN_HAMMING, 0) FFT Sink: Sample Rate 2K Baseband Frequency 1K FFT Size 512 Refresh Rate 30 I need to display shows frequency spectrum centered at 1 GHz. Since I am using decimation of 1M, the frequency is lowered down to 1K. I filter it using FFT bandpass filter with 100 Hz bandwidth. The fft sink shows spectrum at around 1 KHz. The problem is if I do not use decimation, the GRC seems to be very slow (may be processing 1 GHz at GHz sample rate is too much). I need to make a FFT plot showing spectrum at 1 GHz. How Can I accomplish this? Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Spectrum at 1 GHz
your samples rates do not match: usrp2 rate is 100e6/1e6 fft sink rate: 2e3 -Josh On 04/12/2010 12:29 AM, Umair Naeem wrote: I have a query regarding flow graph in GRC. I am trying to get spectrum from DBS_RX daughter board using GRC. I have used three blocks as USRP2 Source -- FFT Filter -- FFT Sink They have following parameters, USRP2 Source: Decimation 1M Frequency 1G Gain (dB) 0 FFT Filter: Decimation 1 Taps firdes.complex_band_pass(1.0, 3000, -0.05e3, 0.05e3, 5, firdes.WIN_HAMMING, 0) FFT Sink: Sample Rate 2K Baseband Frequency 1K FFT Size 512 Refresh Rate 30 I need to display shows frequency spectrum centered at 1 GHz. Since I am using decimation of 1M, the frequency is lowered down to 1K. I filter it using FFT bandpass filter with 100 Hz bandwidth. The fft sink shows spectrum at around 1 KHz. The problem is if I do not use decimation, the GRC seems to be very slow (may be processing 1 GHz at GHz sample rate is too much). I need to make a FFT plot showing spectrum at 1 GHz. How Can I accomplish this? Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] About EEPROM and FX2(68013a) USB interface in USRP
Hi All I am developing a board with gnuradio which is like USRP. It is also use FX2LP(CY7C68013a) and AD9862, and I add some surroundings. I hope that my board can work well with gnuradio, but it seems like it can only support USRP now. So could you please give me some help, if I want to run gnuradio on my board. How should I do with it? Now I do some test with my board. -- When I plug the board to host and run command : lsusb the information list as below: Bus 002 Device 003: ID 0b4:8613 Cypress Semiconductor corp. CY7C68013 EZ-USB FX2 USB 2.0 Development Kit When I plug the USRP it shows Bus 002 Device 003: ID 0xfffe:0x0002 My board is recognized by PC, but VID and PID is different from USRP. What's the problem with it? It means the driver(s) is not correct? Or I should change something in the source or head file? PS: I don't configuration EEPROM with CY7C68013a now. Does this cause some issues? Should I leave it blank? If not, what and how should I burn in it? - When I run benchmark_rx.py, it shows Fail to automatically setup a usrp device. I think it make sense, because the PC doesn't find USRP anyway. Thank you guys all!! Best Regard Sindy ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] gcell on CellBE
Hi, i read the Paper High-Performance SDR: GNU Radio and the IBM Cell Broadband Engine (http://www.ece.umd.edu/~goergen/docs/sdr-gcell.pdf) and under point 4.3.1 the paper says: At this time, all SPEs run the same code, though in the future we expect to dynamically load code into the SPEs How ist the progress in gcell and especially in dynamically offload mechanism for handling jobs for execution on SPEs? Does anybody know, how to set up benchmark-test for gcell ( http://gnuradio.org/redmine/repositories/entry/gnuradio/gcell/apps/benchmark_nop.cc ) to achieve graph results like this: http://gnuradio.org/redmine/attachments/104/R-10231-ps3-20090115-0226.png? Best regards Matthias ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP2-XCVR2450Daughterboard First Program Error
Deal all, in Aalborg University we received last Thursday 3 USRP2 and 3 daughterboards XCVR2450. We started to test them, by running usrp2_fft.py, and in a first moment the output was: usrp2: channel 0 not receiving usrp2::rx_sample() failed then, according to the suggestions done to another user in this forum, who had the same problem, we updated the firmware and the FPGA images and we partially solved the issue. Now it appears the FFT graphical sink, but it doesn't appear the receiving peak at any of the frequencies in the range 2.4-2.5 GHz and 4.9-5.9 GHz, despite we are transmitting at several of those frequencies. Moreover, the following error appears: get fences failed: -1 param:6, val:0 do you have any suggestion? please, let me know. Best Regards, Simone. -- View this message in context: http://old.nabble.com/USRP2-XCVR2450Daughterboard-First-Program-Error-tp28217211p28217211.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Enabling the cognitive radio with GNU Radio+USRP
On 3/7/2010 3:31 PM, Eric Blossom wrote: On Thu, Mar 04, 2010 at 02:45:54PM -0500, Jakub Moskal wrote: Hi everyone, I am trying to use the GNU-Radio+USRP to implement a cognitive radio use case in which radios exchange information (XML-based documents) between each other in order to achieve a defined goal (e.g. to improve connectivity), without disturbing the usual communication. I have several questions regarding this scenario.. In a packet-based communication (e.g. tunnel.py) I imagine that I could transmit my own packets which would include the cognitive information and then receive them on the other end. It would require some special marking of the packets (binary level?) to distinguish the cognitive information from the regular data, so that it could be filtered out on the receiver side. I looked into the tunnel.py, but it seems that it doesn't implement anything higher than the MAC layer - therefore I cannot use it to reliably transfer data, packets get lost or are too small and I would have to split/merge data manually. Would it be possible to combine the tunnel.py with the TCP source/sinks in order to achieve a reliable link? In reality, you'd need some kind of FEC to get the packet error rate down to something you can deal with. Then you could run TCP across the interface. No need for TCP sources or sinks. You've got a (virtual) network interface with an IP address. Just run something that uses TCP on that IP address. Definitely follow Eric's advice and apply some kind of FEC to reduce the packet error rate. When you've done that, the tunnel.py provides you with a TUN/TAP interface, which is a networking interface like eth0 (that is, once you get it working with your Mac, for which I can't be of any help). This will allow you to use a TCP/IP interface to the GNU Radio physical layer. Instead of trying to interleave your cognitive radio control bits into the PHY-layer stream, you should be able to use a TCP port specifically for those purposes. So you'd have two logical links on the TCP layer over the single physical link. Tom ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Enabling the cognitive radio with GNU Radio+USRP
Tom, That is actually what I was going to do. I installed Ubuntu as a dual boot on my Mac and I must say the installation of gnuradio went very smooth, much faster than on the OSX. Too bad this approach is not platform-independent, although it will do for now. Thank you for the advice! Jakub On Mon, Apr 12, 2010 at 8:44 AM, Tom Rondeau trondeau1...@gmail.com wrote: On 3/7/2010 3:31 PM, Eric Blossom wrote: On Thu, Mar 04, 2010 at 02:45:54PM -0500, Jakub Moskal wrote: Hi everyone, I am trying to use the GNU-Radio+USRP to implement a cognitive radio use case in which radios exchange information (XML-based documents) between each other in order to achieve a defined goal (e.g. to improve connectivity), without disturbing the usual communication. I have several questions regarding this scenario.. In a packet-based communication (e.g. tunnel.py) I imagine that I could transmit my own packets which would include the cognitive information and then receive them on the other end. It would require some special marking of the packets (binary level?) to distinguish the cognitive information from the regular data, so that it could be filtered out on the receiver side. I looked into the tunnel.py, but it seems that it doesn't implement anything higher than the MAC layer - therefore I cannot use it to reliably transfer data, packets get lost or are too small and I would have to split/merge data manually. Would it be possible to combine the tunnel.py with the TCP source/sinks in order to achieve a reliable link? In reality, you'd need some kind of FEC to get the packet error rate down to something you can deal with. Then you could run TCP across the interface. No need for TCP sources or sinks. You've got a (virtual) network interface with an IP address. Just run something that uses TCP on that IP address. Definitely follow Eric's advice and apply some kind of FEC to reduce the packet error rate. When you've done that, the tunnel.py provides you with a TUN/TAP interface, which is a networking interface like eth0 (that is, once you get it working with your Mac, for which I can't be of any help). This will allow you to use a TCP/IP interface to the GNU Radio physical layer. Instead of trying to interleave your cognitive radio control bits into the PHY-layer stream, you should be able to use a TCP port specifically for those purposes. So you'd have two logical links on the TCP layer over the single physical link. Tom ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP2-XCVR2450Daughterboard First Program Error
Hi, I think the get fences error is an OpenGL/Video Driver thing, I've seen it when using a laptop with an Intel GMA video chip and just ignored it as things still seemed to work. Can you see a noise floor? Which RF Port are you using on the XCVR2450? (i.e tx/rx or rx only?) Cheers, Tim On Mon, Apr 12, 2010 at 1:41 PM, Simone80 melomelomelom...@libero.itwrote: Deal all, in Aalborg University we received last Thursday 3 USRP2 and 3 daughterboards XCVR2450. We started to test them, by running usrp2_fft.py, and in a first moment the output was: usrp2: channel 0 not receiving usrp2::rx_sample() failed then, according to the suggestions done to another user in this forum, who had the same problem, we updated the firmware and the FPGA images and we partially solved the issue. Now it appears the FFT graphical sink, but it doesn't appear the receiving peak at any of the frequencies in the range 2.4-2.5 GHz and 4.9-5.9 GHz, despite we are transmitting at several of those frequencies. Moreover, the following error appears: get fences failed: -1 param:6, val:0 do you have any suggestion? please, let me know. Best Regards, Simone. -- View this message in context: http://old.nabble.com/USRP2-XCVR2450Daughterboard-First-Program-Error-tp28217211p28217211.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] UHF monitoring
Thanks for reply. I had one more question, if I was just monitoring the usage of channel (it is being used or not at any moment), do I still need to write complex gnuradio scripts? My guess would be that it should be easy to write corresponding scripts since I am not trying to decipher received signal as such. Are such scripts already available in open-source? Thanks a lot and my apologies for not being very radio-literate :( George Johnathan Corgan-2 wrote: On Sun, Apr 11, 2010 at 08:01, schuler101 schuler...@gmail.com wrote: I want to monitor channels with bandwidth 6Mhz. In particular, I want to see time-variant usage of channels in 400-800Mhz range. I do not really want to decipher down the signals. Can you please check if my method is correct or not. Yes. The USRP1 or USRP2 and TVRX daughterboard will allow you to do exactly this. You will need to write a GNU Radio application to analyze the incoming samples and display the information you are interested in, unless the existing spectrum or oscilloscope utilities will give you what you want. Johnathan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio -- View this message in context: http://old.nabble.com/UHF-monitoring-tp28209296p28219151.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Low Pass filter and DPSK params
Hi, I have questions about the parameters in the DBPSK and Low Pass Filter blocks in GRC. Low Pass Filter block: 1) If I set the lowpass filter block to interpolate by a factor of 10 should the sampling rate parameter by set to the input sampling rate or the output sampling rate since they will obviously differ by a factor of 10? 2) If I set the lowpass filter block to interpolate by a factor of 10 is the filtering operation performed before interpolation or after interpolation? (Can the filter get rid of the spectral copies centered at multiples of the input sample rate that are created during interpolation or do I need another lowpass filter afterwards to remove these spectral copies?) DBPSK block: 1) What exactly is the Samples / Symbol parameter mean? I am trying to figure out what the relationship is between the input sample rate (bytes per second) to the output sample rate in (complex samples per second). 2) Since the input is bytes is each bit of the byte converted to a separate symbol meaning get 8 symbols for each imput sample(each byte)? Thanks, Dave ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] About EEPROM and FX2(68013a) USB interface in USRP
On Mon, Apr 12, 2010 at 04:02:43PM +0800, Liang Xin 梁昕 wrote: Hi All I am developing a board with gnuradio which is like USRP. It is also use FX2LP(CY7C68013a) and AD9862, and I add some surroundings. I hope that my board can work well with gnuradio, but it seems like it can only support USRP now. So could you please give me some help, if I want to run gnuradio on my board. How should I do with it? Now I do some test with my board. -- When I plug the board to host and run command : lsusb the information list as below: Bus 002 Device 003: ID 0b4:8613 Cypress Semiconductor corp. CY7C68013 EZ-USB FX2 USB 2.0 Development Kit When I plug the USRP it shows Bus 002 Device 003: ID 0xfffe:0x0002 My board is recognized by PC, but VID and PID is different from USRP. What's the problem with it? It means the driver(s) is not correct? Or I should change something in the source or head file? PS: I don't configuration EEPROM with CY7C68013a now. Does this cause some issues? Should I leave it blank? If not, what and how should I burn in it? Your questions reveal that you don't know have much of an understanding of USB. If you hope to create a USB based device, you should probably spend some time studying the USB 2.0 specs. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] MacPorts and GNU Radio 32-bit
Did you ever make these changes to the portfile for wxgui? @(^.^)@ Ed Michael Dickens wrote: Hi Ed - Thanks for the feedback, it's useful; I don't mind being wrong! I'll have to set up my Mac to do multi-boot (10.5 and 10.6) in order to further test this issue out. That said, the kernel bit-tage doesn't really matter since it's the compiler that determines the applications bit-tage. My guess is that, just like under 10.5, one can compile and execute 64-bit applications ... but under 10.5, 32-bit was the default while under 10.6, 64-bit is the default. !...@#$% Apple for making all of this so %$#! complex ... I guess that's *^% progress; not that I'm giving Linux cudos here for making the 32/64 bit easy I'll see if I can put some changes into the wxgui portfile so that it disallows 64-bit compiling for now, since that seems to be the common factor in the feedback I've received and in my testing. - MLD ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Low Pass filter and DPSK params
On 4/12/2010 3:25 PM, David Barton wrote: Hi, I have questions about the parameters in the DBPSK and Low Pass Filter blocks in GRC. Low Pass Filter block: 1) If I set the lowpass filter block to interpolate by a factor of 10 should the sampling rate parameter by set to the input sampling rate or the output sampling rate since they will obviously differ by a factor of 10? 2) If I set the lowpass filter block to interpolate by a factor of 10 is the filtering operation performed before interpolation or after interpolation? (Can the filter get rid of the spectral copies centered at multiples of the input sample rate that are created during interpolation or do I need another lowpass filter afterwards to remove these spectral copies?) One of my favorite things about GRC is that it allows you to quickly create sample programs to test stuff just like this. You can lay down a signal source, interpolating filter, and FFT and scope sinks to see what happens when you adjust the parameters. Specifically, 1) yes, the sample rate should be at the output rate of the filter (it's generally true that you want to build your filter at the highest sampling rate), and 2) yes, an interpolating filter will interpolate before filtering to remove the spectral images (in actual fact, the implementation details are more complicated, but the effect is the same that the spectral images are removed). DBPSK block: 1) What exactly is the Samples / Symbol parameter mean? I am trying to figure out what the relationship is between the input sample rate (bytes per second) to the output sample rate in (complex samples per second). 2) Since the input is bytes is each bit of the byte converted to a separate symbol meaning get 8 symbols for each imput sample(each byte)? Thanks, Dave With BPSK, yes, you get 8 bits out and each of those bits is converted to 1 symbol. We then interpolate this by the samples_per_symbol = 2 in order to satisfy Nyquist for the pulse shape filtering. So each sample out of the shaping filter is represented by samples_per_symbol number of samples. Play around with this value in GRC and see the effects of using 2, 4 or 8 samples per symbol in both the frequency and time domain. Tom ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] MacPorts and GNU Radio 32-bit
Hi Ed - I never got multi-boot installed, so, no, I haven't gotten those changes in place. That said, the MacPorts folks are discussing ways to get WX stuff to be 64-bit compatible under 10.6, so I might not need to do anything if they succeed soon enough. How badly do you want / need them? - MLD On Apr 12, 2010, at 3:12 PM, Ed Criscuolo wrote: Did you ever make these changes to the portfile for wxgui? ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] ATSC receiving/demodulation/decoding
This is Auburn University's Software Defined Radio Senior Design Team, Our goals are to receive and output FM Radio (which we currently have working) and also to Receive, Decode, and Display HDTV through SDR. We have a USRP1, USRP2, a WBX and a TVRX card, using any combination of this hardware, what would be the best way to receive and decode atsc signals so we can watch hdtv? Some other questions we have: What is the current state of ATSC decoding to watch HDTV? How close to real time can be achieved with the USRP2? For the ATSC part of our project we have been adhering closely to the Readme File found in /gnuradio/gr-atsc/src/python. As far as the results after following the process mentioned in the Readme: Our problems are similar to those I have seen a few posts on the mailing list for already with no replies. The output file is empty. Pipe 5 never seems to get any data. And there is a taps.txt file created which is also empty. We have implemented the suggestions from previous posts to similar problems: We have verified the output of usrp_fft.py as I have seen mentioned. We have tried with latest distributions of LINUX and GNU Radio. - Ubuntu v.9.10 w/ reiserfs, and then after seeing a post on the mailing-list we switched to using xfs - GnuRadio v.3.2.2 - and the git on the bleeding edge of GnuRadio We have tried using both the USRP1 and the USRP2 but with the same problems. Thanks, Stephen Branch and Bobby Black bran...@auburn.edu ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] usrp2_fft.py and changing the gain
Hi all,
I've encountered an issue while running usrp2_fft.py with a dbsrx
daughterboard and I was looking for some insight as to what the cause
is (and a pointer towards a solution if one exists).
When I launch usrp2_fft.py with my dbsrx daughterboard installed, the
system comes up just fine and I see the expected spectrum displayed.
I can change frequencies all day long, and it works exactly as
expected.
However, as soon as I try to change the gain via the usrp2_fft.py GUI,
I get an 'O' character spit out on the USRP2's serial port, and the
GUI completely freezes. I then have to do a manual exit from
the GUI window to get back to a cmd prompt, and can re-launch things from there.
Digging into the USRP2 firmware, the txrx.c main polling loop is where
the putchar('O') gets executed, and there are a few comments
indicating that this is in fact an error case. But it isn't clear to
me what exactly is causing this. The comments indicate that this may
be some sort of overrun condition, and there is a restart_streaming()
call to possibly deal with this issue, but it is commented out in the
current release. I've tried it with a few different daughterboards,
and all seem to result in the same frozen GUI when I go to change the
gain.
Things I've tried (with corresponding results):
-Sometimes when I decimate the data sufficiently (say, to 32 or 64), I
can change the gain on the slider without a problem. But not always.
-I can set the gain from the cmd line when usrp2_fft.py is launched,
and it works just fine.
Anyone else encountered this? Any insights as to what the cause may
be? I'd be happy to dig in and work on a resolution if somebody
points me in the right direction.
Here is my setup:
-GNU Radio git repo cloned ~4/5/2010
-USRP2 + DBSRX, plugged directly into the gigE port on a Lenovo
T400/Core 2 Duo laptop running FC12 (32-bit)...I've also tried this on
an Acer 8940 with a Core I7 running FC12 (64-bit)...same issue on both
Any help would be appreciated...thanks.
--
Regards,
John Orlando
CEO/System Architect
Epiq Solutions
www.epiq-solutions.com
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[Discuss-gnuradio] Frequency not set with ./multi_rx_streaming_samples -f. Please help!
I run the following comamnd: ./multi_rx_streaming_samples -e eth1 -f 5.180G -d 4 -g 20 -N 10 -v -o newtest However, frequency is not set as 5.180G. Basebad_freq is still set to 0. Also, it stuck after 'Receiving 10 samples' and never end.. Anyone has any idea? I appreciate if anyone can help. The detail error message is shown as below: ./multi_rx_streaming_samples -e eth1 -f 5.180G -d 4 -g 20 -N 10 -v -o newtest 1 interfaces make usrp on eth1 lock usrp 1/1 to SMA: done USRP2[0] MAC address: 00:50:c2:85:30:a1 Daughterboard configuration: baseband_freq=0.00 ddc_freq=2000.00 residual_freq=0.004657 inverted=no USRP2 using decimation rate of 4 sync usrp 1/1 to pps: done start_rx_streaming_at usrp 1/1: Receiving 10 samples ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] benchmark tx and rx help
Please check line 113 of benchmark_tx.py data = (pkt_size - 2) * chr(pktno 0xff) Therefore, only the LSB 8 bit of pktno is transmitted in the payload. And please note 257=0x0101, 514=0x0202. So they are payload contents for packet 1 and 2, respectively. You've just missed packet 0. Not quite sure the reason. I guess it might be likely that synchronization at receiver has not been accomplished such that packet 0 is not received correctly. To transmit your own data, you can use --from-file option. The file has to be in binary format. It does not matter what file extension you use. The transmitter just transmits the file contents byte by byte. Regards Kyle Thanks again for replies.. I'm looking for transmitted data (dbpsk mod).For instance (package_size=1500) when pktno=0 (first loop) package should contain 1498 'x00' and package no. At the receiver side i'm looking into the package by reading payload[2:4] but i see 257 for first package 514 for second package and for every new package it is increasing by 257.I expected to see 1 2 3.. and so on ..What can be the reason of this? How shoul i read the coming data at the receiver side? Best Regards Merve ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: interfacing a DSP array card to USRP2
Matt, In our effort to distill the gemac core and related logic, we have pulled out the following module under u2_core SERDES, Dsp core, UART, external RAM interface and the buffer pool The mac is all contained in simple_gemac, and above that in simple_gemac_wrapper: which is instantiated in u2_core. Most of the buffering happens in simple_gemac_wrapper in the fifo_2clock_cascade files. (a) Is any buffering for the gemac done using buffers in the buffer pool or is it ok to eliminate that module all together ? (b) The synthesis report currently shows that 24 BRAM's are being used by the design. Does this sound about right ? Are there modules unrelated to gemac or aeMB that we can pull out, to reduce BRAM usage ? Thanks and Regards, Vikram. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] reuse c++ modules in c++ code
Hi, I am writing a new c++ signal processing block and wondering if I can use existing gnuradio modules in this new module. I know reuse c++ modules in python is easy via swig. When it comes to reusing in c++, what is the best way? I can think of inheritance. But what if I want to use multiple existing modules? Maybe I should use composition, and in my work(), I should call work() of all embeded modules? Regards Kyle ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Transmitting higher power preamble
Hi Brian, Thank you for the reply. I apologize but I could not very well understand the method you suggested. I have not explored much with GNU radio. Could you elaborate more and help me in this regard. I appreciate your time and help. Regards, Neha. On Sun, Apr 11, 2010 at 10:12 AM, Brian Padalino bpadal...@gmail.comwrote: On Sun, Apr 11, 2010 at 10:27 AM, neha kochar nehakoch...@gmail.com wrote: Hi all, Is it possible with GNU Radio to create a transmitter packet that has a higher power preamble at the beginning of the packet? This could allow the receiver to properly detect incoming packets. The data portion of this packet could have reduced transmit power level. I am currently using benchmark tx and rx files. The magnitude of the transmitted complex vector determines the output power (while in the linear range). If you set this magnitude to the value that corresponds to the maximum power output level of the USRP (just before clipping), you should be able to change it such that the data portion is scaled to a lower level. Actually doing this is left as an exercise for the reader. Regards, Neha. Good luck! Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
RE: [Discuss-gnuradio] Spectrum at 1 GHz
Hi Umair There is a setting in the USRP2 source block that lets you set the carrier frequency. This should be 1e9 (i.e. 1G). What is the signal you are trying to receive? Ian -Original Message- From: Umair Naeem [mailto:ar...@student.chalmers.se] Sent: Monday, 12 April 2010 8:22 PM To: Ian Holland Subject: RE: [Discuss-gnuradio] Spectrum at 1 GHz So If I need to see in the baseband region then what should be the parameters of USRP2 source for my case (i.e. Decimation and Frequency). Should I give 1 GHz in the frequency parameter or in the baseband region? Thanks for help... Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. From: Ian Holland [ian.holl...@rlmgroup.com.au] Sent: Monday, April 12, 2010 9:55 AM To: Umair Naeem; discuss-gnuradio@gnu.org Subject: RE: [Discuss-gnuradio] Spectrum at 1 GHz Hi Umair I believe the decimation factor you have chosen is beyond the maximum allowed (I think, from memory this is 512, which is well less than 1M = 1 times 10^6). It seems you are trying to sample the passband signal to show a spectrum at 1 GHz, however a digital-down conversion is performed at the receiver, so you should see a signal at baseband. You should not need to use such a high sampling rate - ideally, Nyquist rate (based on the signal bandwidth when downconveted to baseband) will suffice. Regards Ian. -Original Message- From: discuss-gnuradio-bounces+ian.holland=rlmgroup.com...@gnu.org [mailto:discuss-gnuradio-bounces+ian.holland=rlmgroup.com...@gnu.org] On Behalf Of Umair Naeem Sent: Monday, 12 April 2010 4:59 PM To: discuss-gnuradio@gnu.org Subject: [Discuss-gnuradio] Spectrum at 1 GHz I have a query regarding flow graph in GRC. I am trying to get spectrum from DBS_RX daughter board using GRC. I have used three blocks as USRP2 Source -- FFT Filter -- FFT Sink They have following parameters, USRP2 Source: Decimation 1M Frequency 1G Gain (dB) 0 FFT Filter: Decimation 1 Taps firdes.complex_band_pass(1.0, 3000, -0.05e3, 0.05e3, 5, firdes.WIN_HAMMING, 0) FFT Sink: Sample Rate 2K Baseband Frequency 1K FFT Size 512 Refresh Rate 30 I need to display shows frequency spectrum centered at 1 GHz. Since I am using decimation of 1M, the frequency is lowered down to 1K. I filter it using FFT bandpass filter with 100 Hz bandwidth. The fft sink shows spectrum at around 1 KHz. The problem is if I do not use decimation, the GRC seems to be very slow (may be processing 1 GHz at GHz sample rate is too much). I need to make a FFT plot showing spectrum at 1 GHz. How Can I accomplish this? Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Using a custom block
On Mon, Apr 12, 2010 at 4:32 PM, Kurt Holmquist kurtholmqu...@hotmail.comwrote: Thank you for the response. I would like to use as GRC blocks the blocks that I create as described in How to Write a Signal Processing Block. This is a somewhat unconventional situation in that I need a way for an installed application (i. e. grc) to use a locally created component, sort of the opposite of the normal situation. I think the XML file for the block should look something like: ?xml version=1.0? block nameSquare2/name keyhowto_square2_ff/key categoryHOWTO/category importimport howto/import makehowto.square2_ff()/make sink namein/name typefloat/type /sink source nameout/name typefloat/type /source /block When I copy this file into the directory where GRC stores the block XML files (/usr/local/share/gnuradio/grc/blocks), GRC makes a Square2 block available for use. However, when I attempt to execute a flow graph that includes this block, it fails as follows: Generating: /home/kurt/gnuradio/grc/wav_file_to_speaker.py Executing: /home/kurt/gnuradio/grc/wav_file_to_speaker.py Traceback (most recent call last): File /home/kurt/gnuradio/grc/wav_file_to_speaker.py, line 17, in module import howto ImportError: No module named howto * Where I need help is that I don't know how to set up python and/or environment so that python can import these components. * Thanks again for any help you can provide. Kurt, I think you want to write *from gnuradio* import howto Karthik ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Why no phase ambiguity in digital-bert...
Hi All I have been studying up on the Costas loop, and have a couple of queries as to the benchmark_tx.py and benchmark_rx.py as a result. Firstly, for BPSK, there should in theory be a 180 deg. phase ambiguity when using a Costas loop. Why does this not seem to occur with the benchmark_rx.py example? Is this related somehow to the PN code introduced by the scrambler. Secondly, I came across another post in which it was mentioned the Costas loop should only operate on a single sample per symbol. However, as I read the source code, it seems as though it is actually passed sps samples per symbol, where sps 1. Have I misread something here? Any help in these matters would be greatly appreciated. Thanks Ian. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
